Sizu Home › Calculators › Z-Score and Percentile
Optional: the same standing on another scale
Enter a value, a mean and a standard deviation, then press Calculate.
From the book, Chapter 5. z = (value − mean) ÷ standard deviation. Ana’s chemistry 78 (mean 65, SD 8) is z = 1.63; her history 84 (mean 72, SD 10) is z = 1.20. The percentile assumes the group’s values follow a bell curve; for lopsided data, use the real list of values instead.
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